Automatic generation of application domain specific graphical programs

ABSTRACT

System and method for generating an application domain specific graphical program. A graphical user interface (GUI) for specifying functionality of a graphical program in an application domain is displayed, where the GUI corresponds specifically to the application domain. User input to the GUI specifying the functionality of the graphical program is received, and the graphical program generated in response, where the graphical program is executable to perform the specified functionality, and comprises multiple interconnected graphical program nodes that visually represent the graphical program functionality. The GUI includes graphical interface elements operable to indicate and/or specify, e.g., via user input, respective attributes of the graphical program such as timing, triggering, analog and/or digital input/output (I/O), resource allocation, processing option, inclusion of one or more external files, and one or more target devices, among others, and may determine the graphical interface elements based on the specified one or more target devices.

FIELD OF THE INVENTION

The present invention relates to the field of graphical programming, andmore particularly to a system and method of use for an applicationdomain specific tool for specifying desired program functionality for agraphical program in the application domain, and programmaticallygenerating graphical source code implementing the specifiedfunctionality.

DESCRIPTION OF THE RELATED ART

Traditionally, high level text-based programming languages have beenused by programmers in writing application programs. Many different highlevel text-based programming languages exist, including BASIC, C, C++,Java, FORTRAN, Pascal, COBOL, ADA, APL, etc. Programs written in thesehigh level text-based languages are translated to the machine languagelevel by translators known as compilers or interpreters. The high leveltext-based programming languages in this level, as well as the assemblylanguage level, are referred to herein as text-based programmingenvironments.

Increasingly, computers are required to be used and programmed by thosewho are not highly trained in computer programming techniques. Whentraditional text-based programming environments are used, the user'sprogramming skills and ability to interact with the computer systemoften become a limiting factor in the achievement of optimal utilizationof the computer system.

There are numerous subtle complexities which a user must master beforehe can efficiently program a computer system in a text-basedenvironment. The task of programming a computer system to model orimplement a process often is further complicated by the fact that asequence of mathematical formulas, steps or other procedures customarilyused to conceptually model a process often does not closely correspondto the traditional text-based programming techniques used to program acomputer system to model such a process. In other words, the requirementthat a user program in a text-based programming environment places alevel of abstraction between the user's conceptualization of thesolution and the implementation of a method that accomplishes thissolution in a computer program. Thus, a user often must substantiallymaster different skills in order to both conceptualize a problem orprocess and then to program a computer to implement a solution to theproblem or process. Since a user often is not fully proficient intechniques for programming a computer system in a text-based environmentto implement his solution, the efficiency with which the computer systemcan be utilized often is reduced.

To overcome the above shortcomings, various graphical programmingenvironments now exist which allow a user to construct a graphicalprogram or graphical diagram, also referred to as a block diagram. U.S.Pat. Nos. 4,901,221; 4,914,568; 5,291,587; 5,301,301; and 5,301,336;among others, to Kodosky et al disclose a graphical programmingenvironment which enables a user to easily and intuitively create agraphical program. Graphical programming environments such as thatdisclosed in Kodosky et al can be considered a higher and more intuitiveway in which to interact with a computer. A graphically basedprogramming environment can be represented at a level above text-basedhigh level programming languages such as C, Basic, Java, etc.

A user may assemble a graphical program by selecting various icons ornodes which represent desired functionality, and then connecting thenodes together to create the program. The nodes or icons may beconnected by lines representing data flow between the nodes, controlflow, or execution flow. Thus the block diagram may include a pluralityof interconnected icons such that the diagram created graphicallydisplays a procedure or method for accomplishing a certain result, suchas manipulating one or more input variables and/or producing one or moreoutput variables. In response to the user constructing a diagram orgraphical program using the block diagram editor, data structures and/orprogram instructions may be automatically constructed which characterizean execution procedure that corresponds to the displayed procedure. Thegraphical program may be compiled or interpreted by a computer.

A graphical program may have a graphical user interface. For example, increating a graphical program, a user may create a front panel or userinterface panel. The front panel may include various graphical userinterface elements or front panel objects, such as user interfacecontrols and/or indicators, that represent or display the respectiveinput and output that will be used by the graphical program, and mayinclude other icons which represent devices being controlled.

Thus, graphical programming has become a powerful tool available toprogrammers. Graphical programming environments such as the NationalInstruments LabVIEW product have become very popular. Tools such asLabVIEW have greatly increased the productivity of programmers, andincreasing numbers of programmers are using graphical programmingenvironments to develop their software applications. In particular,graphical programming tools are being used for test and measurement,data acquisition, process control, man machine interface (MMI),supervisory control and data acquisition (SCADA) applications, modeling,simulation, image processing/machine vision applications, and motioncontrol, among others.

As graphical programming environments have matured and grown inpopularity and complexity, it has become increasingly desirable toprovide high-level tools which help a user create a graphical program.It also becomes increasingly desirable to integrate graphicalprogramming environments with other applications and programmingenvironments. In order to provide the desired tools or the desiredintegration, it would be greatly desirable to provide the ability todynamically or programmatically generate a graphical program or aportion of a graphical program. For example, for various applications,it would be desirable to provide various types of program information toa program, wherein the program information specifies functionality of agraphical program (or portion of a graphical program) to beprogrammatically generated.

As described above, a user typically creates a graphical program withina graphical programming environment by interactively or manually placingicons or nodes representing the desired blocks of functionality on adiagram, and connecting the icons/nodes together to represent one ormore of the data flow, control flow, and/or execution flow of theprogram. The ability to programmatically generate a graphical program inresponse to program information would enable a graphical program orgraphical program portion to automatically be generated without thistype of interactive user input. For example, it would be desirable forthe user to be able to specify program functionality at a high level viaone or more graphical user interface (GUI) panels, and to thenprogrammatically generate a graphical program or graphical programportion implementing the specified program functionality, where thegraphical program may be targeted for various target platforms, such asFPGAs, embedded devices, and general purpose computer systems, amongothers.

SUMMARY OF THE INVENTION

Various embodiments of a tool, e.g., an application assistant, aredescribed that may be used to specify or otherwise define theorganization of features in an application, i.e., in a graphicalprogram. In a preferred embodiment, an application assistant may bedesigned to build block diagrams for a specific class of applications,such as control loops, timer/counters, I/O, signal generation, etc. Thecreator of the assistant preferably has domain knowledge about theindividual features and how they relate to one another for this class ofapplications. Therefore the assistant preferably knows which featuresare defined as input resources and which are defined as output resourcesso that they may be placed correctly in the block diagram. In oneembodiment, a simple assistant may provide the ability to configuretiming, triggering, and I/O features. In more advanced embodiments,extensions to this basic functionality may include advanced I/O types,embedded processing, and inclusion of user created features, resourceallocation, processing options, inclusion of external files, and targetdevices for the graphical program, among others. Further details of anexample application assistant and its use are provided below.

The method described below is preferably performed by an applicationassistant (or equivalent) that includes a GUI for displaying informationto a user and for receiving input from the user, e.g., via a pluralityof fields, sections, or panels displayed on a computer monitor. Themethod below is described with respect to a control loop application,where, for example, a first portion of the application is targeted forexecution on a programmable hardware element, such as an FPGA, and asecond portion of the application is targeted for execution on a hostcomputer system, where the first and second portions execute in acoordinated manner to perform the application domain specificfunctionality, e.g., the control loop. However, it should be noted thatthis is but one example of an application assistant, and that othertypes of application assistants (or equivalent) are also contemplatedfor any application domain desired. Application domains contemplatedinclude, but are not limited to, control loops, timer/counters, dataacquisition, machine vision, and so forth. Note that the specificity ofthe various domains contemplated may vary widely, and that domains mayalso be hierarchical.

For example, at a high level, control usually refers to maintaining asystem at a setpoint through the use of command outputs and feedbackinputs. An application assistant may be created that deals with thisdomain at a fairly simple and general level. For example, in oneembodiment, the assistant may provide or facilitate a single timed loop,and may allow the user to specify the inputs to be sampled and theoutputs to be driven, where, for example, all of the processing occursin the host. This example assistant may be used for many types ofcontrol applications.

However, there are many sub-domains that may benefit from more specificapplication assistants. These more specific application assistants(e.g., control assistants) may offer options that are tuned orcorrespond to the more narrow domains. For example, consider a servomotor positioning controller. This type of controller operates to rotatea motor in a controlled fashion from one position to another. The systemtypically includes forward and reverse limit switches used to indicatethe end of travel, and implemented as digital inputs. Instead of justpresenting generic digital I/O, the assistant may ask which lines arespecifically to be used as limit switches. The feedback mechanism forthe majority of servo motor applications is some form of quadratureencoder. Although the assistant may present other options for feedback,in some embodiments, it may offer a richer set of quadrature interfacesthan the generic assistant might, and may offer the quadrature interfaceas the default selection.

Thus, in various embodiments, application assistants may be provided forany domain or sub-domain desired, including, for example, control, e.g.,control loops, motion control, etc., timer/counters; measurement, e.g.,data acquisition, waveform generation, etc., data analysis, e.g.,pattern matching, image and/or signal processing, etc., machine vision,hardware in the loop simulation, simulation, and embedded systems, amongothers. Note that these application domains and sub-domains are meant tobe exemplary only, and are not intended to limit the fields, domains, orsub-domains, to which application assistants may be directed.

An application domain specific graphical user interface (GUI) may bedisplayed for specifying functionality of a graphical program in anapplication domain, wherein the GUI corresponds specifically to theapplication domain, and preferably includes a plurality of graphicalinterface elements, e.g., controls and/or indicators, operable tospecify and/or indicate respective attributes of the graphical program.

User input may be received to the GUI, e.g., via a pointing device,keyboard, voice, and/or any other type of user interface means, to theGUI, e.g., by manipulating controls, entering alphanumeric data, etc.,to specify desired functionality or otherwise configure the applicationas desired. For example, the user input to the GUI may specify suchaspects of the graphical program as timing, triggering, analoginput/output (I/O), digital I/O, resource allocation, mathematicalalgorithms and/or other processing, one or more target devices, and/orinclusion of one or more external files in the graphical program, e.g.,user created subVIs or third party programs, among others.

In one embodiment, the GUI may be dynamic with respect to the user input(or with respect to input from other sources). For example, in anembodiment where the user input to the GUI specifies one or more targetdevices for the graphical program, the plurality of graphical interfaceelements (comprised in and displayed by the GUI) may be determined basedon the specified one or more target devices for the graphical program,where the plurality of graphical interface elements correspond torespective attributes of the graphical program appropriate to the one ormore target devices. In other words, if the specified target device (ordevices) has no digital resources, i.e., no digital lines, then the GUImay not include graphical interface elements for specifying digitalresources.

In another embodiment, once the user has specified the functionality ofthe graphical program, the application assistant may determine one ormore suitable target devices for the graphical program based on thespecified functionality, and the GUI may indicate the one or moresuitable target devices, e.g., via a list box or other means. User inputmay then be received selecting at least a subset of the one or moresuitable target devices for deployment and execution of the graphicalprogram. In other words, the assistant may be operable to restrict thepossible target devices presented to the user to those capable ofsupporting the specified functionality. Thus, if digital resources arespecified by the user, the GUI preferably presents target devices forselection that include such digital resources.

In one embodiment, at least a portion of the graphical program istargeted for execution on a programmable hardware element. The GUI maybe operable to display an estimated utilization of the programmablehardware element by the graphical program.

Then, the graphical program may be programmatically or automaticallygenerated in response to the user input. The graphical program comprisesa plurality of interconnected graphical program nodes that visuallyrepresents the functionality of the graphical program, and is executableto perform the specified functionality. In one embodiment, the assistantmay generate both the FPGA diagram intended for the hardware and the RTdiagram targeting the processor. Thus, in this example controlapplication, the generated graphical program is a distributed graphicalprogram comprising a first portion and a second portion, where the firstportion is targeted for execution on a first device, and where thesecond portion is targeted for execution on a second device, and wherethe first portion and the second portion are respectively executable onthe first device and the second device to perform the specifiedfunctionality in a cooperative manner.

In various embodiments, the graphical program code may be generatedusing any of various methods or techniques. For example, the applicationassistant may analyze the inputs provided by the user and determineappropriate graphical program elements corresponding to the specifiedfunctionality, and may configure the determined graphical programelements accordingly, including setting values of one or more parametersand interconnecting (“wiring”) the graphical program elements toimplement the correct input/output relationships between them. In otherembodiments, in generating the graphical program, the applicationassistant may generate one or more intermediate structures, e.g., datastructures or files. For example, the application assistant may analyzethe user input, generate one or more data structures based on theanalysis, and generate the graphical program based on the one or moredata structures. As another example, the application assistant maygenerate a program specification based on the user input, then parse andanalyze the program specification, and generate the graphical programbased on the analysis.

In one embodiment, configuration information for the graphical programmay be stored, e.g., in one or more of the intermediate structuresdescribed above, or may be generated based on the graphical program. Inone embodiment, the configuration information may be stored in thegraphical program. For example, the graphical program may be tagged withthe configuration information. Then, at some later date, the graphicalprogram may be analyzed, e.g., by the assistant or some other tool, todetermine the original configuration of the graphical program. Thegraphical program may comprise one or more features, each of which maycomprise a respective one or more graphical program elements. In apreferred embodiment, the configuration information specifies thegraphical program at a feature level, i.e., as opposed to the graphicalprogram element level. This configuration information may be useful forsubsequent modification of the graphical program.

In various cases, the graphical program code generated by theapplication assistant may be a fully working program, or may not be acomplete program. As an example, the application assistant may generatevarious graphical program elements or nodes that, in conjunction withadditional graphical program elements, may comprise a complete program.However, the creation of the partial graphical program may make itrelatively easy for the user to complete the graphical program. In stillother cases, it may be desirable to programmatically generate only agraphical code portion, e.g., that aids the user in program development.

In one embodiment, the assistant may use scripting to place specifiedfeatures or functionality into the graphical program, e.g., into one ormore block diagrams. For example, the assistant may determine whichfeatures are necessary based on the user input (or programspecification), and then may create a batch file or script (or multiplefiles or scripts) to automate the graphical program generation. Eachfeature may then be scripted or generated and placed without any furtheruser interaction. In one embodiment, the script or scripts may begenerated based on the analysis of the user input. Alternatively, thescripts may have been previously created, where the appropriate scriptsare determined based on the analysis of the user input, and retrievedfor execution, e.g., via a look-up table. Thus, in one embodiment, theuser input may be analyzed, and one or more scripts executed to generatethe graphical program.

In one embodiment, generating the graphical program may includeanalyzing the user input, and invoking one or more low level assistantsto generate the graphical program, where each of the low levelapplication assistants executes a respective one or more scripts togenerate respective portions of the graphical program. In other words,the application assistant may include, or may operate in conjunctionwith, a plurality of other assistants, specifically, lower levelassistants, where, for example, each assistant is specific or directedto a particular functional aspect of the application. Each low levelassistant may assist in the scripting or generation of graphical programcode for a respective sub-domain of the application assistant'sapplication domain. Thus, the various assistants (including theapplication assistant) may comprise a hierarchy of assistants.

Finally, the graphical program may optionally be executed to perform thespecified functionality. For example, in one embodiment, user inputinvoking execution of the graphical program may be received, and thegraphical program executed, in response to the invoking. As noted above,in one embodiment, at least a portion of the graphical program may betargeted for execution on a programmable hardware element. Moregenerally, in various embodiments, various portions of the graphicalprogram may be targeted to respective different targets, including, forexample, computers, programmable hardware elements, such as FPGAs, PDAs,embedded systems, such as smart sensors, etc., and/or any other type oftarget capable of executing graphical program code. For example,different scripts may be created specifically for generating graphicalprogram portions or features for execution on particular targets.Alternatively, scripts may be created that are agnostic with regards totarget platforms, but which may be configured or specified, to generategraphical program features for specific targets. In other words, thesame script may be configured to generate graphical program code aimedat different targets.

In one embodiment, the application assistant may facilitate modificationof a previously created block diagram or graphical program. For example,in one embodiment, user input may be received to the GUI specifyingimport of a previously created graphical program. The previously createdgraphical program may then be imported in response to the user inputspecifying the import, configuration information for the importedgraphical program analyzed (programmatically), and the GUI may displayrespective attributes of the imported graphical program based on theanalyzing, and, for example, used to populate the graphical interfaceelements of the GUI with appropriate data. The user may then specifydesired (new) functionality for the imported graphical program, asdescribed above, where the application assistant then generates thegraphical program (i.e., the modified imported graphical program) basedon the specified functionality.

BRIEF DESCRIPTION OF THE DRAWINGS

A better understanding of the present invention can be obtained when thefollowing detailed description of the preferred embodiment is consideredin conjunction with the following drawings, in which:

FIG. 1A illustrates a computer system operable to execute a graphicalprogram according to an embodiment of the present invention;

FIG. 1B illustrates a network system comprising two or more computersystems that may implement an embodiment of the present invention;

FIG. 2A illustrates an instrumentation control system including variousI/O interface options, according to one embodiment of the invention;

FIG. 2B illustrates an industrial automation system including variousI/O interface options, according to one embodiment of the invention;

FIG. 3A is a high level block diagram of an exemplary system which mayexecute or utilize graphical programs;

FIG. 3B illustrates an exemplary system which may perform control and/orsimulation functions utilizing graphical programs;

FIG. 4 is an exemplary block diagram of the computer systems of FIGS.1A, 1B, 2A and 2B and 3B;

FIG. 5 is a flowchart diagram of a method for programmaticallygenerating a graphical program in a specific application domain,according to one embodiment;

FIG. 6 illustrates an application assistant for creating a graphicalprogram for use in a specific application domain, according to oneembodiment;

FIG. 7 illustrates exemplary timing models for a control loop, accordingto one embodiment;

FIGS. 8A and 8B illustrate programmatically generated block diagrams,according to one embodiment;

FIG. 8C illustrates exemplary block diagram features, according to oneembodiment;

FIGS. 9A and 9B illustrate generation of analog input and analog outputfeatures in a block diagram, according to one embodiment.

While the invention is susceptible to various modifications andalternative forms specific embodiments are shown by way of example inthe drawings and are herein described in detail. It should be understoodhowever, that drawings and detailed description thereto are not intendedto limit the invention to the particular form disclosed, but on thecontrary the invention is to cover all modifications, equivalents andalternative following within the spirit and scope of the presentinvention as defined by the appended claims.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS INCORPORATION BYREFERENCE

The following references are hereby incorporated by reference in theirentirety as though fully and completely set forth herein.

U.S. Pat. No. 5,481,741 titled “Method and Apparatus for ProvidingAttribute Nodes in a Graphical Data Flow Environment,” issued on Jan. 2,1996.

U.S. Pat. No. 6,064,812 titled “System and Method for DevelopingAutomation Clients Using a Graphical Data Flow Program,” issued on May16, 2000.

U.S. Pat. No. 6,102,965 titled “System and Method for ProvidingClient/Server Access to Graphical Programs,” issued on Aug. 15, 2000.

U.S. patent application Ser. No. 09/136,123 titled “System and Methodfor Accessing Object Capabilities in a Graphical Program” filed Aug. 18,1998.

U.S. patent application Ser. No. 09/518,492 titled “System and Methodfor Programmatically Creating a Graphical Program”, filed Mar. 3, 2000.

U.S. patent application Ser. No. 09/595,003 titled “System and Methodfor Automatically Generating a Graphical Program to Implement aPrototype,” filed Jun. 13, 2000.

U.S. patent application Ser. No. 09/745,023 titled “System and Methodfor Programmatically Generating a Graphical Program in Response toProgram Information,” filed Dec. 20, 2000.

U.S. patent application Ser. No. 08/912,445 titled “Embedded GraphicalProgramming System” filed on Aug. 18, 1997, whose inventors were JeffreyL. Kodosky, Darshan Shah, Samson DeKey, and Steve Rogers.

U.S. patent application Ser. No. 08/912,427 titled “System and Methodfor Converting Graphical Programs Into Hardware Implementations” filedon Aug. 18, 1997, whose inventors were Jeffrey L. Kodosky, Hugo Andrade,Brian Keith Odom, and Cary Paul Butler.

U.S. patent application Ser. No. 10/177,553 titled “TargetDevice-Specific Syntax and Semantic Analysis For a Graphical Program”filed on Jun. 21, 2002, whose inventors were Newton G. Petersen andDarshan K. Shah.

Terms

The following is a glossary of terms used in the present application:

Memory Medium—Any of various types of memory devices or storage devices.The term “memory medium” is intended to include an installation medium,e.g., a CD-ROM, floppy disks 104, or tape device; a computer systemmemory or random access memory such as DRAM, DDR RAM, SRAM, EDO RAM,Rambus RAM, etc.; or a non-volatile memory such as a magnetic media,e.g., a hard drive, or optical storage. The memory medium may compriseother types of memory as well, or combinations thereof. In addition, thememory medium may be located in a first computer in which the programsare executed, or may be located in a second different computer whichconnects to the first computer over a network, such as the Internet. Inthe latter instance, the second computer may provide programinstructions to the first computer for execution. The term “memorymedium” may include two or more memory mediums which may reside indifferent locations, e.g., in different computers that are connectedover a network.

Carrier Medium—a memory medium as described above, as well as signalssuch as electrical, electromagnetic, or digital signals, conveyed via acommunication medium such as a bus, network and/or a wireless link.

Programmable Hardware Element—includes various types of programmablehardware, reconfigurable hardware, programmable logic, orfield-programmable devices (FPDs), such as one or more FPGAs (FieldProgrammable Gate Arrays), or one or more PLDs (Programmable LogicDevices), such as one or more Simple PLDs (SPLDs) or one or more ComplexPLDs (CPLDs), or other types of programmable hardware. A programmablehardware element may also be referred to as “reconfigurable logic”.

Medium—includes one or more of a memory medium, carrier medium, and/orprogrammable hardware element; encompasses various types of mediums thatcan either store program instructions/data structures or can beconfigured with a hardware configuration program.

Program—the term “program” is intended to have the full breadth of itsordinary meaning. The term “program” includes 1) a software programwhich may be stored in a memory and is executable by a processor or 2) ahardware configuration program useable for configuring a programmablehardware element.

Software Program—the term “software program” is intended to have thefull breadth of its ordinary meaning, and includes any type of programinstructions, code, script and/or data, or combinations thereof, thatmay be stored in a memory medium and executed by a processor. Exemplarysoftware programs include programs written in text-based programminglanguages, such as C, C++, Pascal, Fortran, Cobol, Java, assemblylanguage, etc.; graphical programs (programs written in graphicalprogramming languages); assembly language programs; programs that havebeen compiled to machine language; scripts; and other types ofexecutable software. A software program may comprise two or moresoftware programs that interoperate in some manner.

Hardware Configuration Program—a program, e.g., a netlist or bit file,that can be used to program or configure a programmable hardwareelement.

Graphical Program—A program comprising a plurality of interconnectednodes or icons, wherein the plurality of interconnected nodes or iconsvisually indicate functionality of the program.

The following provides examples of various aspects of graphicalprograms. The following examples and discussion are not intended tolimit the above definition of graphical program, but rather provideexamples of what the term “graphical program” encompasses:

The nodes in a graphical program may be connected in one or more of adata flow, control flow, and/or execution flow format. The nodes mayalso be connected in a “signal flow” format, which is a subset of dataflow.

Exemplary graphical program development environments which may be usedto create graphical programs include LabVIEW, DasyLab, DiaDem andMatrixx/SystemBuild from National Instruments, Simulink from theMathWorks, VEE from Agilent, WiT from Coreco, Vision Program Managerfrom PPT Vision, SoftWIRE from Measurement Computing, Sanscript fromNorthwoods Software, Khoros from Khoral Research, SnapMaster from HEMData, VisSim from Visual Solutions, ObjectBench by SES (Scientific andEngineering Software), and VisiDAQ from Advantech, among others.

The term “graphical program” includes models or block diagrams createdin graphical modeling environments, wherein the model or block diagramcomprises interconnected nodes or icons that visually indicate operationof the model or block diagram; exemplary graphical modeling environmentsinclude Simulink, SystemBuild, VisSim, Hypersignal Block Diagram, etc.

A graphical program may be represented in the memory of the computersystem as data structures and/or program instructions. The graphicalprogram, e.g., these data structures and/or program instructions, may becompiled or interpreted to produce machine language that accomplishesthe desired method or process as shown in the graphical program.

Input data to a graphical program may be received from any of varioussources, such as from a device, unit under test, a process beingmeasured or controlled, another computer program, a database, or from afile. Also, a user may input data to a graphical program or virtualinstrument using a graphical user interface, e.g., a front panel.

A graphical program may optionally have a GUI associated with thegraphical program. In this case, the plurality of interconnected nodesare often referred to as the block diagram portion of the graphicalprogram.

Node—In the context of a graphical program, an element that may beincluded in a graphical program. A node may have an associated icon thatrepresents the node in the graphical program, as well as underlying codeor data that implements functionality of the node. Exemplary nodesinclude function nodes, terminal nodes, structure nodes, etc. Nodes maybe connected together in a graphical program by connection icons orwires.

Data Flow Graphical Program (or Data Flow Diagram)—A graphical programor diagram comprising a plurality of interconnected nodes, wherein theconnections between the nodes indicate that data produced by one node isused by another node.

Graphical User Interface—this term is intended to have the full breadthof its ordinary meaning. The term “Graphical User Interface” is oftenabbreviated to “GUI”. A GUI may comprise only one or more input GUIelements, only one or more output GUI elements, or both input and outputGUI elements.

The following provides examples of various aspects of GUIs. Thefollowing examples and discussion are not intended to limit the ordinarymeaning of GUI, but rather provide examples of what the term “graphicaluser interface” encompasses:

A GUI may comprise a single window having one or more GUI Elements, ormay comprise a plurality of individual GUI Elements (or individualwindows each having one or more GUI Elements), wherein the individualGUI Elements or windows may optionally be tiled together.

A GUI may be associated with a graphical program. In this instance,various mechanisms may be used to connect GUI Elements in the GUI withnodes in the graphical program. For example, when Input Controls andOutput Indicators are created in the GUI, corresponding nodes (e.g.,terminals) may be automatically created in the graphical program orblock diagram. Alternatively, the user can place terminal nodes in theblock diagram which may cause the display of corresponding GUI Elementsfront panel objects in the GUI, either at edit time or later at runtime. As another example, the GUI may comprise GUI Elements embedded inthe block diagram portion of the graphical program.

Front Panel—A Graphical User Interface that includes input controls andoutput indicators, and which enables a user to interactively control ormanipulate the input being provided to a program, and view output of theprogram, while the program is executing.

A front panel is a type of GUI. A front panel may be associated with agraphical program as described above.

In an instrumentation application, the front panel can be analogized tothe front panel of an instrument. In an industrial automationapplication the front panel can be analogized to the MMI (Man MachineInterface) of a device. The user may adjust the controls on the frontpanel to affect the input and view the output on the respectiveindicators.

Graphical User Interface Element—an element of a graphical userinterface, such as for providing input or displaying output. Exemplarygraphical user interface elements comprise input controls and outputindicators

Input Control—a graphical user interface element for providing userinput to a program. Exemplary input controls comprise dials, knobs,sliders, input text boxes, etc.

Output Indicator—a graphical user interface element for displayingoutput from a program. Exemplary output indicators include charts,graphs, gauges, output text boxes, numeric displays, etc. An outputindicator is sometimes referred to as an “output control”.

Computer System—any of various types of computing or processing systems,including a personal computer system (PC), mainframe computer system,workstation, network appliance, Internet appliance, personal digitalassistant (PDA), television system, grid computing system, or otherdevice or combinations of devices. In general, the term “computersystem” can be broadly defined to encompass any device (or combinationof devices) having at least one processor that executes instructionsfrom a memory medium.

Measurement Device—includes instruments, data acquisition devices, smartsensors, and any of various types of devices that are operable toacquire and/or store data. A measurement device may also optionally befurther operable to analyze or process the acquired or stored data.Examples of a measurement device include an instrument, such as atraditional stand-alone “box” instrument, a computer-based instrument(instrument on a card) or external instrument, a data acquisition card,a device external to a computer that operates similarly to a dataacquisition card, a smart sensor, one or more DAQ or measurement cardsor modules in a chassis, an image acquisition device, such as an imageacquisition (or machine vision) card (also called a video capture board)or smart camera, a motion control device, a robot having machine vision,and other similar types of devices. Exemplary “stand-alone” instrumentsinclude oscilloscopes, multimeters, signal analyzers, arbitrary waveformgenerators, spectroscopes, and similar measurement, test, or automationinstruments.

A measurement device may be further operable to perform controlfunctions, e.g., in response to analysis of the acquired or stored data.For example, the measurement device may send a control signal to anexternal system, such as a motion control system or to a sensor, inresponse to particular data. A measurement device may also be operableto perform automation functions, i.e., may receive and analyze data, andissue automation control signals in response.

FIG. 1A—Computer System

FIG. 1A illustrates a computer system 82 suitable to implement variousembodiments of the present invention. More specifically, computer system82 may execute software for programmatically or automatically generatingat least a portion of a graphical program in response to user input,where for example, the software implements a graphical software tool.One embodiment of a method for receiving user input specifyingapplication domain specific functionality for a graphical program andprogrammatically generating the graphical program that implements thespecified functionality is described below with reference to FIG. 6.

As shown in FIG. 1A, the computer system 82 may include a display deviceoperable to display a graphical user interface (GUI) whereby the usermay interact with the software to specify and create graphical programcode for a specific application domain. The display device may also beoperable to display graphical programs as the graphical programs arecreated and/or executed. The display device may also be operable todisplay a graphical user interface or front panel of the graphicalprogram during execution of the graphical program. The graphical userinterface may comprise any type of graphical user interface, e.g.,depending on the computing platform.

The computer system 82 may include a memory medium(s) on which one ormore computer programs or software components according to oneembodiment of the present invention may be stored. For example, thememory medium may store one or more programs, e.g., graphical programs,which are executable to perform the methods described herein. Also, thememory medium may store a graphical programming development environmentapplication used to create and/or execute such graphical programs. Thememory medium may also store operating system software, as well as othersoftware for operation of the computer system. Various embodimentsfurther include receiving or storing instructions and/or dataimplemented in accordance with the foregoing description upon a carriermedium.

The computer system 82 preferably includes or stores a computer program,referred to herein as an application assistant. One embodiment of amethod for programmatically generating a graphical program is describedbelow. It should be noted that although the application assistant isdescribed herein as a standalone program, in various embodiments, theapplication assistant may be implemented in different ways, including,but not limited to, a standalone tool, a plug-in for a graphicaldevelopment environment, an integrated portion of a developmentenvironment, a graphical application programming interface (API), and soforth.

In one embodiment, the application assistant may be implemented as aself-contained program or application that includes all necessaryprogram logic for generating the graphical program. In anotherembodiment, the application assistant may comprise a client portion anda server portion (or client program and server program), wherein theclient portion may request or direct the server portion to performvarious aspects of the interface and/or generation functionality. Forexample, the client portion may utilize an API provided by the serverportion in order to generate the graphical program. In other words, theclient portion may perform calls to the API provided by the serverportion, and the server portion may execute functions or routines boundto these calls to generate the graphical program. In one embodiment, theserver portion may be an instance of a graphical programming developmentenvironment application. For example, the LabVIEW graphical programmingdevelopment environment application enables client programs to interfacewith a LabVIEW server in order to programmatically generate or modifygraphical programs.

In some embodiments, rather than generating the graphical programdirectly, the application assistant may generate one or more scripts orscripting components (referred to collectively herein as a “script”),which may then be executed to generate the graphical program. Thus, inone embodiment, the application assistant may operate as a scriptingtool (or equivalent) that may be used to generate or create a script(e.g., a script or scripting component), where the script comprises agraphical program generation (GPG) program.

As used herein, the term “GPG program” is intended to include any ofvarious implementations of a program (or programs) that are executableto programmatically generate a graphical program based on receivedprogram information. For example, the term “GPG program” is intended toinclude an embodiment in which the GPG program is a self-containedprogram or application (not implemented as a client/server program) thatincludes all necessary program logic for programmatically generating agraphical program. The term “GPG program” is also intended to include anembodiment in which a combination of a client portion (or clientprogram) and server portion (or server program) operate together toprogrammatically generate the graphical program. The term “GPG program”is also intended to include other program implementations.

In an embodiment in which a client program interfaces with a serverprogram to generate the graphical program (or scripts), the serverprogram may execute on the same computer system as the client program ormay execute on a different computer system, e.g., a different computersystem connected via a network. For example, in FIG. 1B, the clientprogram may execute on the computer system 82, and the server programmay execute on the computer system 90. In this case, the graphicalprogram, and/or script, may be created on the computer system 82, or 90,or on a different computer system. Thus, the application assistant maybe distributed over a plurality of computers, or may be executed on asingle computer.

It is noted that the application assistant may be implemented using anyof various programming technologies or methodologies. Where theapplication assistant is implemented as client and server programs, eachof these programs may utilize procedure-based techniques,component-based techniques, and/or object-oriented techniques, amongothers. The programs may be written using any combination of text-basedor graphical programming languages. Also, the programs may be writtenusing distributed modules or components so that each program may resideon any combination of computer system 82, computer system 86, and othercomputer systems connected to the network 84. Also, in variousembodiments, the client program may interface with the server programthrough a proxy software component or program.

FIG. 1B—Computer Network

FIG. 1B illustrates a system including a first computer system 82 thatis coupled to a second computer system 90. The computer system 82 may beconnected through a network 84 (or a computer bus) to the secondcomputer system 90. The computer systems 82 and 90 may each be any ofvarious types, as desired. The network 84 can also be any of varioustypes, including a LAN (local area network), WAN (wide area network),the Internet, or an Intranet, among others. The computer systems 82 and90 may execute the application assistant in a distributed fashion. Forexample, computer 82 may execute a first portion of the applicationassistant and computer system 90 may execute a second portion of theapplication assistant. As another example, computer 82 may display thegraphical user interface of the application assistant and computersystem 90 may execute the core functionality of the applicationassistant.

In embodiments where the application assistant generates a script, thescript may be executed to generate graphical program code in a graphicalprogram, where, for example, the graphical user interface of thegraphical program may be displayed on a display device of the computersystem 82, and the block diagram may execute on a device 190 connectedto the computer system 82. The device 190 may include a programmablehardware element and/or may include a processor and memory medium whichmay execute a real time operating system. In one embodiment, thegraphical program may be downloaded and executed on the device 190. Forexample, an application development environment with which the graphicalprogram is associated may provide support for downloading a graphicalprogram for execution on the device in a real time system.

Exemplary Systems

Embodiments of the present invention may be involved with performingtest and/or measurement functions; controlling and/or modelinginstrumentation or industrial automation hardware; modeling andsimulation functions, e.g., modeling or simulating a device or productbeing developed or tested, etc. Exemplary test applications where thegenerated graphical program may be used include hardware-in-the-looptesting and rapid control prototyping, among others.

However, it is noted that the present invention can be used for aplethora of applications and is not limited to the above applications,but rather it is contemplated that application assistants may be createdand used for any application domains desired. In other words,applications discussed in the present description are exemplary only,and the present invention may be used in any of various types ofsystems. Thus, the system and method of the present invention isoperable to be used in any of various types of applications, includingthe control of other types of devices such as multimedia devices, videodevices, audio devices, telephony devices, Internet devices, etc. Inother embodiments, the application assistant may be used to generategraphical program code for general purpose software applications such asword processing, spreadsheets, network control, network monitoring,financial applications, games, etc.

FIGS. 2A and 2B—Instrumentation and Industrial Automation Systems

FIGS. 2A and 2B illustrate exemplary systems which may store or use anapplication assistant (optionally with a server program) that isoperable to create a graphical program or a portion of a graphicalprogram (possibly via scripting). Also, these systems may execute aprogrammatically generated graphical program. For example, the graphicalprogram may perform an instrumentation function, such as a test andmeasurement function or an industrial automation function. It is notedthat the application assistant, the server program, and/or a generatedgraphical program may be stored in or used by any of various other typesof systems as desired and may implement any function or application asdesired. Thus, FIGS. 2A and 2B are exemplary only.

FIG. 2A illustrates an exemplary instrumentation control system 100which may implement embodiments of the invention. The system 100comprises a host computer 82 which connects to one or more instruments.The host computer 82 may comprise a CPU, a display screen, memory, andone or more input devices such as a mouse or keyboard as shown. Thecomputer 82 may operate with the one or more instruments to analyze,measure or control a unit under test (UUT) or process 150.

The one or more instruments may include a GPIB instrument 112 andassociated GPIB interface card 122, a data acquisition board 114 andassociated signal conditioning circuitry 124, a VXI instrument 116, aPXI instrument 118, a video device or camera 132 and associated imageacquisition (or machine vision) card 134, a motion control device 136and associated motion control interface card 138, and/or one or morecomputer based instrument cards 142, among other types of devices. Thecomputer system may couple to and operate with one or more of theseinstruments. The instruments may be coupled to a unit under test (UUT)or process 150, or may be coupled to receive field signals, typicallygenerated by transducers. The system 100 may be used in a dataacquisition and control application, in a test and measurementapplication, an image processing or machine vision application, aprocess control application, a man-machine interface application, asimulation application, or a hardware-in-the-loop validationapplication, among others.

FIG. 2B illustrates an exemplary industrial automation system 160 whichmay implement embodiments of the invention. The industrial automationsystem 160 is similar to the instrumentation or test and measurementsystem 100 shown in FIG. 2A. Elements which are similar or identical toelements in FIG. 2A have the same reference numerals for convenience.The system 160 may comprise a computer 82 which connects to one or moredevices or instruments. The computer 82 may comprise a CPU, a displayscreen, memory, and one or more input devices such as a mouse orkeyboard as shown. The computer 82 may operate with the one or moredevices to a process or device 150 to perform an automation function,such as MMI (Man Machine Interface), SCADA (Supervisory Control and DataAcquisition), portable or distributed data acquisition, process control,advanced analysis, or other control, among others.

The one or more devices may include a data acquisition board 114 andassociated signal conditioning circuitry 124, a PXI instrument 118, avideo device 132 and associated image acquisition card 134, a motioncontrol device 136 and associated motion control interface card 138, afieldbus device 170 and associated fieldbus interface card 172, a PLC(Programmable Logic Controller) 176, a serial instrument 182 andassociated serial interface card 184, or a distributed data acquisitionsystem, such as the Fieldpoint system available from NationalInstruments, among other types of devices.

In one embodiment, the application assistant and/or the resultinggraphical program that is programmatically generated may be designed fordata acquisition/generation, analysis, and/or display, and forcontrolling or modeling instrumentation or industrial automationhardware. For example, in one embodiment, the National InstrumentsLabVIEW graphical programming development environment application, whichprovides specialized support for developers of instrumentationapplications, may act as the server program. In this embodiment, theclient program may be a software program that receives and processesprogram information and invokes functionality of the LabVIEW graphicalprogramming development environment. The client program may also be aprogram involved with instrumentation or data acquisition.

However, as noted above, the present invention can be used for aplethora of applications and is not limited to instrumentation orindustrial automation applications. In other words, FIGS. 2A and 2B areexemplary only, and graphical programs for any of various types ofpurposes may be generated by an application assistant designed for anyof the various types of purposes, wherein the programs are stored in andexecute on any of various types of systems. A specific example of anapplication assistant directed at control loops, and graphical programsgenerated thereby are discussed below.

FIG. 3A is a high level block diagram of an exemplary system which mayexecute or utilize graphical programs. FIG. 3A illustrates a generalhigh-level block diagram of a generic control and/or simulation systemwhich comprises a controller 92 and a plant 94. The controller 92represents a control system/algorithm the user may be trying to develop.The plant 94 represents the system the user may be trying to control.For example, if the user is designing an ECU for a car, the controller92 is the ECU and the plant 94 is the car's engine (and possibly othercomponents such as transmission, brakes, and so on.) As shown, a usermay create a graphical program that specifies or implements thefunctionality of one or both of the controller 92 and the plant 94. Forexample, a control engineer may use a modeling and simulation tool tocreate a model (graphical program) of the plant 94 and/or to create thealgorithm (graphical program) for the controller 92.

FIG. 3B illustrates an exemplary system which may perform control and/orsimulation functions. As shown, the controller 92 may be implemented bya computer system 82 or other device (e.g., including a processor andmemory medium and/or including a programmable hardware element) thatexecutes or implements a graphical program. In a similar manner, theplant 94 may be implemented by a computer system or other device 144(e.g., including a processor and memory medium and/or including aprogrammable hardware element) that executes or implements a graphicalprogram, or may be implemented in or as a real physical system, e.g., acar engine.

In one embodiment of the invention, one or more graphical programs maybe created which are used in performing rapid control prototyping. RapidControl Prototyping (RCP) generally refers to the process by which auser develops a control algorithm and quickly executes that algorithm ona target controller connected to a real system. The user may develop thecontrol algorithm using a graphical program, and the graphical programmay execute on the controller 92, e.g., on a computer system or otherdevice. The computer system 82 may be a platform that supports real timeexecution, e.g., a device including a processor that executes a realtime operating system (RTOS), or a device including a programmablehardware element.

In one embodiment of the invention, one or more graphical programs maybe created which are used in performing Hardware in the Loop (HIL)simulation. Hardware in the Loop (HIL) refers to the execution of theplant model 94 in real time to test operation of a real controller 92.For example, once the controller 92 has been designed, it may beexpensive and complicated to actually test the controller 92 thoroughlyin a real plant, e.g., a real car. Thus, the plant model (implemented bya graphical program) is executed in real time to make the realcontroller 92 “believe” or operate as if it is connected to a realplant, e.g., a real engine.

In the embodiments of FIGS. 2A, 2B, and 3B above, one or more of thevarious devices may couple to each other over a network, such as theInternet. In one embodiment, the user operates to select a target devicefrom a plurality of possible target devices for programming orconfiguration using a graphical program. Thus the user may create agraphical program on a computer and use (execute) the graphical programon that computer or deploy the graphical program to a target device (forremote execution on the target device) that is remotely located from thecomputer and coupled to the computer through a network.

Graphical software programs which perform data acquisition, analysisand/or presentation, e.g., for measurement, instrumentation control,industrial automation, modeling, or simulation, such as in theapplications shown in FIGS. 2A and 2B, may be referred to as virtualinstruments.

FIG. 4—Computer System Block Diagram

FIG. 4 is a block diagram representing one embodiment of the computersystem 82 and/or 90 illustrated in FIGS. 1A and 1B, or computer system82 shown in FIG. 2A or 2B. It is noted that any type of computer systemconfiguration or architecture can be used as desired, and FIG. 4illustrates a representative PC embodiment. It is also noted that thecomputer system may be a general purpose computer system, a computerimplemented on a card installed in a chassis, or other types ofembodiments. Elements of a computer not necessary to understand thepresent description have been omitted for simplicity.

The computer may include at least one central processing unit or CPU(processor) 160 which is coupled to a processor or host bus 162. The CPU160 may be any of various types, including an x86 processor, e.g., aPentium class, a PowerPC processor, a CPU from the SPARC family of RISCprocessors, as well as others. A memory medium, typically comprising RAMand referred to as main memory, 166 is coupled to the host bus 162 bymeans of memory controller 164. The main memory 166 may store theapplication assistant operable to programmatically or automaticallygenerate at least a portion of a graphical program, e.g., graphicalcode, in accordance with a user-specified configuration. The main memorymay also store operating system software, as well as other software foroperation of the computer system.

The host bus 162 may be coupled to an expansion or input/output bus 170by means of a bus controller 168 or bus bridge logic. The expansion bus170 may be the PCI (Peripheral Component Interconnect) expansion bus,although other bus types can be used. The expansion bus 170 includesslots for various devices such as described above. The computer 82further comprises a video display subsystem 180 and hard drive 182coupled to the expansion bus 170.

As shown, a device 190 may also be connected to the computer. The device190 may include a processor and memory which may execute a real timeoperating system. The device 190 may also or instead comprise aprogrammable hardware element. The computer system may be operable todeploy a graphical program to the device 190 for execution of thegraphical program on the device 190. The deployed graphical program maytake the form of graphical program instructions or data structures thatdirectly represents the graphical program. Alternatively, the deployedgraphical program may take the form of text code (e.g., C code)generated from the graphical program. As another example, the deployedgraphical program may take the form of compiled code generated fromeither the graphical program or from text code that in turn wasgenerated from the graphical program.

Application Assistant

In one embodiment, a tool, e.g., an application assistant, may be usedto specify or otherwise define the organization of features in anapplication, i.e., in a graphical program. In a preferred embodiment, anapplication assistant may be designed to build block diagrams for aspecific class of applications, such as control loops, timer/counters,I/O, signal generation, etc. The creator of the assistant preferably hasdomain knowledge about the individual features and how they relate toone another for this class of applications. For example, a control loopmay have independent triggers for input and output resources. Thereforethe assistant preferably knows which features are defined as inputresources and which are defined as output resources so that they may beplaced correctly in the block diagram. In one embodiment, a simpleassistant may provide the ability to configure timing, triggering, andI/O features. In more advanced embodiments, extensions to this basicfunctionality may include advanced I/O types, embedded processing, andinclusion of user created features, resource allocation, processingoptions, inclusion of external files, and target devices for thegraphical program, among others. Further details of an exampleapplication assistant and its use are provided below.

FIG. 5—Programmatic Generation of an Application Domain SpecificGraphical Program

FIG. 5 is a high-level flowchart of a method for programmaticallygenerating a graphical program, where the graphical programfunctionality is specific to an application domain. As noted above, themethod described below is preferably performed by an applicationassistant (or equivalent) that includes a GUI for displaying informationto a user and for receiving input from the user, e.g., via a pluralityof fields, sections, or panels displayed on a computer monitor. Notethat in various embodiments, some of the steps shown may be performedconcurrently, in a different order than shown, or omitted. Additionalsteps may also be performed as desired.

The method of FIG. 5 is described below with respect to a control loopapplication, where, for example, a first portion of the application istargeted for execution on a programmable hardware element, such as anFPGA, and a second portion of the application is targeted for executionon a host computer system, where the first and second portions executein a coordinated manner to perform the application domain specificfunctionality, e.g., the control loop. However, it should be noted thatthis is but one example of an application assistant, and that othertypes of application assistants (or equivalent) are also contemplatedfor any application domain desired. Application domains contemplatedinclude, but are not limited to, control loops, timer/counters, dataacquisition, machine vision, and so forth. Note that the specificity ofthe various domains contemplated may vary widely, and that domains mayalso be hierarchical. For example, consider control. At a high level,control usually refers to maintaining a system at a setpoint through theuse of command outputs and feedback inputs. An application assistant maybe created that deals with this domain at a fairly simple and generallevel. For example, in one embodiment, the assistant may provide orfacilitate a single timed loop, and may allow the user to specify theinputs to be sampled and the outputs to be driven, where, for example,all of the processing occurs in the host. This example assistant may beused for many types of control applications.

However, there are many sub-domains that may benefit from more specificapplication assistants. These more specific application assistants(e.g., control assistants) may offer options that are tuned orcorrespond to the more narrow domains. For example, consider a servomotor positioning controller. This type of controller operates to rotatea motor in a controlled fashion from one position to another. The systemtypically includes forward and reverse limit switches used to indicatethe end of travel, and implemented as digital inputs. Instead of justpresenting generic digital I/O, the assistant may ask which lines arespecifically to be used as limit switches. The feedback mechanism forthe majority of servo motor applications is some form of quadratureencoder. Although the assistant may present other options for feedback,in some embodiments, it may offer a richer set of quadrature interfacesthan the generic assistant might, and may offer the quadrature interfaceas the default selection.

Thus, in various embodiments, application assistants may be provided forany domain or sub-domain desired, including, for example, control, e.g.,control loops, motion control, etc., timer/counters; measurement, e.g.,data acquisition, waveform generation, etc., data analysis, e.g.,pattern matching, image and/or signal processing, etc., machine vision,hardware in the loop simulation, simulation, and embedded systems, amongothers. Note that these application domains and sub-domains are meant tobe exemplary only, and are not intended to limit the fields, domains, orsub-domains, to which application assistants may be directed.

In 502, an application domain specific graphical user interface (GUI)may be displayed, e.g., on a display device, such as a computer monitor.In other words, a graphical user interface (GUI) may be displayed forspecifying functionality of a graphical program in an applicationdomain, wherein the GUI corresponds specifically to the applicationdomain. In a preferred embodiment, the GUI includes a plurality ofgraphical interface elements, e.g., controls and/or indicators, operableto specify and/or indicate respective attributes of the graphicalprogram.

FIG. 6 illustrates one embodiment of such a GUI, where the GUI shown isspecific to control loops. In other words, FIG. 6 illustrates oneembodiment of a control assistant for configuring a control applicationtargeted for at least partial execution on an FPGA, although it shouldbe noted that the embodiment shown is intended to be exemplary only, andis not intended to limit the control assistant to any particular form,appearance, or functionality. Similarly, as noted above, the controlassistant is provided as an example application assistant, and is notintended to limit the domains of application to any domain or set ofdomains.

As is well known to those skilled in the art, control applicationstypically wait for data to be ready, read the inputs, perform someprocessing, write the outputs, and start waiting again. The timing(including triggering and synchronization) and I/O are typicallyperformed in hardware, while the control algorithm runs in software on aprocessor. In one embodiment, the application assistant may display, andmay also allow the user to specify, a timing model for the application.

As FIG. 6 shows, at the top of the GUI is shown a timing modelindicating timing and triggering for the application, as well as variousfields for specifying other aspects of the desired functionality,described in more detail below. In this example, controls are providedin the timing model section for specifying a loop trigger and an outputtrigger, where each trigger may be specified as internal, external, orsoftware-based. In this example, the output trigger may also bespecified to be the loop trigger. Note that in other embodiments, e.g.,in other application assistants, other trigger options may be presented,e.g., analog or digital triggering, and so forth.

As FIG. 6 indicates, the timing model shown specifies that an internaltrigger initiates output from the previous iteration as well as input tothe host for the current iteration. There are numerous common timingconfigurations suitable for use with a control loop, a few of which areillustrated in FIG. 7. As FIG. 7 illustrates, each of the timing modelsis represented by a timing diagram that specifies timing and triggeringfor each iteration of the control loop. Note that in these diagrams,time increases from left to right, and two iterations of the controlloop are shown.

For example, in the first (top) timing model diagram, an internaltrigger is used to initiate output from the previous iteration as wellas input to the host for the current iteration, as indicated. In otherwords, the two internal triggers shown are actually the same trigger onsuccessive iterations of the loop. Note that this timing model is thesame as that of FIG. 6. In the second (middle) timing model diagram, aninternal trigger initiates input to the host, while a software trigger(executing on the host) triggers output. In the third (bottom) timingmodel diagram, an external trigger initiates output from the previousiteration as well as input to the host for the current iteration.

As FIG. 6 also shows, in this embodiment, controls are provided forspecifying, loading, and saving, the project within which theapplication is being developed. Controls are also provided forspecifying analog and digital I/O resources, e.g., features, lines orchannels (analog input, analog output, and digital resources sections),etc. For example, in this embodiment, up to 8 analog input features andup to 8 analog output features may be specified for inclusion in theapplication. In the digital resources section, 12 banks of DIO lines(0-11) are provided, where each bank includes 8 lines, as well as asection for specifying particular lines for a given bank. As is wellknown in the art, DIO lines may be used as simple lines, or may be usedto implement more complex DIO resources, such as counters, filters,etc., such as, for example, event counters, quadrature encoders, and soforth.

In this particular example, a section, labeled “microDAQ Slots”, is alsoprovided for specifying use of external modules or cartridges, e.g.,external I/O resources. For example, one or more of the DIO lines may beused to control selected modules, where, for example, the DIO lines maycontrol a passive backplane which couples to the modules. Thus, in oneembodiment, external I/O resources may also be incorporated into thecontrol application functionality.

In this example, one portion of the control application being configuredis intended for execution on an FPGA, as mentioned above, while anotherportion of the application is intended for execution under a real timeoperating system, such as, for example LabVIEW RT. Thus, controls,labeled “Generate FPGA VI” and “Generate RT VI”, may be provided togenerate each of these portions separately. Note that the controlapplication being configured in this example corresponds to blockdiagrams illustrated in FIGS. 8A and 8B, and described in more detailbelow.

In 504, user input may be received to the GUI, where the user inputspecifies the functionality of the graphical program. In other words,the user may provide input, e.g., via a pointing device, keyboard,voice, and/or any other type of user interface means, to the GUI, e.g.,by manipulating controls, entering alphanumeric data, etc., to specifydesired functionality or otherwise configure the application as desired.For example, the user input to the GUI may specify such aspects of thegraphical program as timing, triggering, analog input/output (I/O),digital I/O, resource allocation, mathematical algorithms and/or otherprocessing, one or more target devices, and/or inclusion of one or moreexternal files in the graphical program, e.g., user created subVIs orthird party programs, among others.

For example, an external files option may enable the user to includefunctionality in the scripted diagram or graphical program that is notincluded in the assistant itself. For example, it may not be feasiblefor the assistant to include every type of counter that could beimagined in a selection list. Thus, for example, the user may create acustom counter and access it through the assistant as an external file,e.g., in the form of a VI, a VHDL file, or any other means of specifyingfunctionality.

There may also be cases where the custom function is not created by theuser, but rather by a third party, in which this case the user may stillinclude the third party function or file through the external filesapproach. Third party functions or files are theoretically no differentthan what the user could create himself, but may be more feasible for acustomer to purchase rather than create in some circumstances.

Examples of processing options include, but are not limited to, inlineprocesses, such as, for example, inline processing of filtering, peakdetection, etc., in an analog input stream, or higher level processingsuch as the inclusion of a PID loop that uses multiple resources. Inother words, different types of processing may be selected by the userand implemented in the FPGA.

For example, in one example of a “no processing” case, the user mayconfigure a control application to simply sample an analog input andreturn the data to the host. The control algorithm is preferablyperformed on the host, and the output data written back to the FPGA,which may then pass the data to an analog output. In this particularexample, the user may decide that the returned data are too noisy, andso may add inline processing in the FPGA to apply to the analog inputdata, e.g., a low pass filter, so that the FPGA VI (or other type ofprogram deployed to the FPGA) returns filtered data to the host insteadof the raw data. The user may then decide that the control loop is tooslow with the main control algorithm executing on the host, and so maydecide to move the algorithm directly into the FPGA. Once deployed tothe FPGA, the algorithm may execute to receive the filtered analog inputdata, perform its processing, and write to the analog output. Note thatin various embodiments, the processing functions may operate on singleor multiple resources, the resources may be of different types, and theresources themselves may actually be the results of processing performedon lower level resources.

In a preferred embodiment, in specifying timing for the graphicalprogram, the user input may specify a timing model for the graphicalprogram, where the GUI is operable to display a graphical representationof the timing model in response to the user input, as described aboveand illustrated in FIGS. 6 and 7.

In one embodiment, the GUI may be dynamic with respect to the user input(or with respect to input from other sources). For example, in anembodiment where the user input to the GUI specifies one or more targetdevices for the graphical program, the plurality of graphical interfaceelements (comprised in and displayed by the GUI) may be determined basedon the specified one or more target devices for the graphical program,where the plurality of graphical interface elements correspond torespective attributes of the graphical program appropriate to the one ormore target devices. In other words, if the specified target device (ordevices) has no digital resources, i.e., no digital lines, then the GUImay not include graphical interface elements for specifying digitalresources.

In another embodiment, once the user has specified the functionality ofthe graphical program, the application assistant may determine one ormore suitable target devices for the graphical program based on thespecified functionality, and the GUI may indicate the one or moresuitable target devices, e.g., via a list box or other means. User inputmay then be received selecting at least a subset of the one or moresuitable target devices for deployment and execution of the graphicalprogram. In other words, the assistant may be operable to restrict thepossible target devices presented to the user to those capable ofsupporting the specified functionality. Thus, if digital resources arespecified by the user, the GUI preferably presents target devices forselection that include such digital resources.

As also described above, in one embodiment, at least a portion of thegraphical program is targeted for execution on a programmable hardwareelement. In one embodiment, the GUI may able operable to display anestimated utilization of the programmable hardware element by thegraphical program. For example, in one embodiment, as the user specifiesthe various options, e.g., the analog/digital I/O resources, etc., theassistant may estimate the utilization of the FPGA for this specificapplication and may display this information, e.g., via an indicator,such as a bar or “thermometer” indicator, shown in FIG. 6, and labeled“Estimated Utilization”. This immediate feedback may help the user makebetter decisions about resource allocations and selections withoutwaiting for a long compile step.

Then, in 506, the graphical program may be programmatically orautomatically generated in response to the user input. The graphicalprogram comprises a plurality of interconnected graphical program nodesthat visually represents the functionality of the graphical program, andis executable to perform the specified functionality.

Following the control example of FIG. 6, in one embodiment, theassistant may generate both the FPGA diagram intended for the hardwareand the RT diagram targeting the processor. As noted above, in thebottom right portion of the GUI are controls for specifying the targetplatform for the generated application or VI, i.e., an FPGA or a realtime OS (e.g., LabVIEW RT), running on the host computer. Thus, in apreferred embodiment, the GUI may be further operable to receive userinput specifying deployment of the graphical program to one or moretarget devices, and the application assistant may deploy the graphicalprogram to the one or more target devices in response to receiving theuser input specifying the deployment of the graphical program. Thisfeature may substantially speed development for the user, who canpresumably then focus attention and effort on the algorithms of theapplication, rather than low-level logistics such as data transfer andsynchronization. In one embodiment, the GUI may be further operable todisplay the generated graphical program, an example of which isdescribed below with reference to FIGS. 8A and 8B. In a furtherembodiment, the GUI may be further operable to receive user inputinvoking execution of the graphical program, and the graphical programexecuted on the one or more target devices in response to the invoking.

As noted above, in this example control application, the generatedgraphical program is a distributed graphical program comprising a firstportion and a second portion, where the first portion is targeted forexecution on a first device, and wherein the second portion is targetedfor execution on a second device, and where the first portion and thesecond portion are respectively executable on the first device and thesecond device to perform the specified functionality in a cooperativemanner.

As described above, a graphical program preferably includes a blockdiagram comprising a plurality of interconnected graphical programelements, e.g., nodes or icons. FIGS. 8A and 8B illustrate examplegraphical programs designed to operate in conjunction as a controlapplication, which typically waits for data to be ready, reads theinputs, performs some processing, writes the outputs, and starts waitingagain. The timing and I/O are typically performed in hardware, executingon a programmable hardware element (e.g., an FPGA), while the controlalgorithm executes in software on a processor (e.g., computer system82). Thus, FIG. 8A illustrates the first portion of the graphicalprogram, targeted for deployment and execution on a programmablehardware element, e.g., an FPGA, and FIG. 8B illustrates the secondportion of the graphical program, targeted for deployment and executionon a host computer system.

As mentioned above, the FPGA block diagram (FIG. 8A) defines thebehavior of the hardware. According to the specified timing model, theblock diagram should include a timer to control how often the I/O issampled, the actual I/O functionality, and a notification mechanism (aninterrupt in this case) to tell the software that data are ready. Notethat in the embodiment of FIG. 6, the GUI is operable to display anestimated utilization of the programmable hardware element by the firstportion of the graphical program, e.g., by the block diagram of FIG. 8A.

In this example, the FPGA is assumed to be connected to fixed I/Oresources, such as analog inputs, analog outputs, and digital inputs andoutputs. A “personality” may be loaded into the FPGA to define theoverall behavior of the board. This personality may be created using adevelopment environment, such as LabVIEW FPGA, which creates a hardwareimplementation of a graphical program, e.g., of a LabVIEW diagram. Thus,the LabVIEW FPGA diagram preferably defines the behavior of thehardware. As shown, the example diagram of FIG. 8A includes a timer tocontrol how often the I/O is sampled, the actual I/O (analog input (AI)and analog output (AO)), and a notification mechanism (an interrupt inthis case) to tell the software that data are ready. As FIG. 8A alsoshows, a timing or sequence structure encloses these elements andensures that their respective functions are performed in an appropriatesequence. Note that the timing structure includes three frames withinwhich features, i.e., graphical program elements implementing thefeatures, may be executed in an ordered sequence.

As noted above, FIG. 8B is an example block diagram, in this case, aLabVIEW RT diagram, targeted for execution by a processor. This diagramdefines the behavior of the software, downloading the FPGA personality(the diagram of FIG. 8A) to the FPGA board, setting the timer to thedesired loop rate, and starting the LabVIEW FPGA diagram running. AsFIG. 8B also shows, the diagram then waits in a loop for data to beready, reads the inputs, writes the outputs, and then starts waitingagain. Graphical program elements implementing any algorithm to beperformed on the data may be placed between the AI and AO elements (VIs)in the diagram.

Each of the block diagrams shown includes various graphical programfeatures providing respective functionalities for the block diagrams.Each of these features, also referred to as feature templates, typicallyincludes one or more graphical program elements. FIG. 8C illustrates thegraphical program features used in the block diagram of FIG. 8A,specifically, a timing structure, analog input, analog output, a timer,and an interrupt. Note that a feature may include a plurality ofgraphical program elements. For example, the analog input feature shownincludes an analog input node (labeled “AI”, with a waveform and arrowicon), an input icon, e.g., a constant indicating a device orchannel/line, and an output icon or terminal (I16—a sixteen bitinteger), e.g., for providing output to an indicator. Thus, thegeneration of the graphical program may be performed in terms of programfeatures, rather than at the level of individual graphical programelements. Note that the features shown are meant to be exemplary only,and are not intended to limit features to any particular set of forms orfunctionalities, but rather, contemplated features may include anydefinable functionality that can be represented or implemented in agraphical program. Thus, a graphical program may include a plurality ofdefined features. Conversely, a user may construct a graphical programfrom a set of graphical program features, described below.

In various embodiments, the graphical program code may be generatedusing any of various methods or techniques. For example, in oneembodiment, the application assistant may analyze the inputs provided bythe user in 504 and determine appropriate graphical program elementscorresponding to the specified functionality, and may configure thedetermined graphical program elements accordingly, including settingvalues of one or more parameters and interconnecting (“wiring”) thegraphical program elements to implement the correct input/outputrelationships between them.

In other embodiments, in generating the graphical program, theapplication assistant may generate one or more intermediate structures,e.g., data structures or files. For example, the application assistantmay analyze the user input (of 504), generate one or more datastructures based on the analysis, and generate the graphical programbased on the one or more data structures. As another example, theapplication assistant may generate a program specification based on theuser input, then parse and analyze the program specification, andgenerate the graphical program based on the analysis.

More generally, generating the graphical program may comprise generatingone or more files defining or describing the graphical program code. Forexample, the program files may specify information such as a set ofnodes that the graphical program uses, interconnections among thesenodes, programmatic structures such as loops, etc. In other cases, theprogram files may store various data structures, e.g., in binary form,which the graphical programming environment uses to directly representthe graphical program. Thus, in programmatically generating thegraphical program code, the application assistant may programmaticallygenerate one or more files representing the graphical program, where,for example, these files may be structured or formatted appropriatelyfor a particular graphical programming environment.

In one embodiment, configuration information for the graphical programmay be stored. The configuration information may be comprised in one ormore of the intermediate structures described above, or may be generatedbased on the graphical program. In one embodiment, the configurationinformation may be stored in a configuration file; however, this mayrequire that the configuration file be kept with, or otherwisemaintained with, the graphical program. Thus, in a preferred embodiment,the configuration information may be stored in the graphical program.For example, the graphical program may be tagged with the configurationinformation. Then, at some later date, the graphical program tags may beanalyzed, e.g., by the assistant or some other tool, to determine theoriginal configuration of the graphical program.

As noted above, in one embodiment, the graphical program may compriseone or more features, each of which may comprise a respective one ormore graphical program elements. In a preferred embodiment, theconfiguration information specifies the graphical program at a featurelevel, i.e., as opposed to the graphical program element level. Thisconfiguration information may be useful for subsequent modification ofthe graphical program, described below.

In various cases, the graphical program code generated by theapplication assistant may be a fully working program. Thus, the user mayload the generated graphical program into the graphical programmingenvironment, execute the program, etc. In other cases, the generatedgraphical program code may not be a complete program. As an example, theapplication assistant may generate various graphical program elements ornodes that, in conjunction with additional graphical program elements,may comprise a complete program. However, the creation of the partialgraphical program may make it relatively easy for the user to completethe graphical program. In still other cases, it may be desirable toprogrammatically generate only a graphical code portion, e.g., that aidsthe user in program development.

In one embodiment, the assistant may use scripting to place specifiedfeatures or functionality into the graphical program, e.g., into one ormore block diagrams. For example, the assistant may determine whichfeatures are necessary based on the user input (or programspecification), and then may create a batch file or script (or multiplefiles or scripts) to automate the graphical program generation. Eachfeature may then be scripted or generated and placed without any furtheruser interaction. In one embodiment, the script or scripts may begenerated based on the analysis of the user input. Alternatively, thescripts may have been previously created, where the appropriate scriptsare determined based on the analysis of the user input, and retrievedfor execution, e.g., via a look-up table. Thus, in one embodiment, theuser input may be analyzed, and one or more scripts executed to generatethe graphical program.

FIGS. 9A and 9B illustrate generation or scripting of program features,specifically, analog input and analog output features in a timingfeature, into a block diagram of a graphical program, according to oneembodiment. As FIG. 9A shows, starting with a blank block diagram (topdiagram), an AI script or script portion may be created or configured togenerate two instances of an AI feature in a timing feature, and mayexecute to generate the two AI feature instances in the timing structureas configured by the user, here shown in the middle frame of the timingstructure (bottom diagram).

FIG. 9B illustrates placement of AO features in the block diagram ofFIG. 9A. As FIG. 9B shows, in this example, an AO script has beencreated or configured to generate two instances of an AO feature in atiming feature. However, as the bottom diagram of FIG. 9B shows, ratherthan generating the two AO features in a nested (second) timing feature,the script recognizes that a timing feature of the specified type hasalready been included in the block diagram, and so generates the two AOfeatures in the previously generated timing feature. Thus, in oneembodiment, the script (and/or the application assistant) may execute togenerate graphical program features in a context sensitive manner.

In one embodiment, generating the graphical program may includeanalyzing the user input, and invoking one or more low level assistantsto generate the graphical program, where each of the low levelapplication assistants executes a respective one or more scripts togenerate respective portions of the graphical program. In other words,the application assistant may include, or may operate in conjunctionwith, a plurality of other assistants, specifically, lower levelassistants, where, for example, each assistant is specific or directedto a particular functional aspect of the application. Said another way,each low level assistant may assist in the scripting or generation ofgraphical program code for a respective sub-domain of the applicationassistant's application domain. Thus, the various assistants (includingthe application assistant) may comprise a hierarchy of assistants. Asone example of such a hierarchy, a counter/timer application assistantmay include or operate in conjunction with, such low level assistants asan event counter assistant, a quadrature encoding assistant, and aperiod measurement assistant, among others. Note that these low levelassistants are meant to be exemplary only, and are not intended to limitthe application assistant or low level assistants to any particularform, function, or organization.

Referring back to the control application example, in one embodiment,the generation of the two LabVIEW diagrams (FPGA and RT of FIGS. 8A and8B, respectively) may be performed in four steps. First the assistantmay generate the FPGA diagram, e.g., using the graphical programfeatures or scripts. The assistant may then generate the RT diagramusing the appropriate (presumably different) graphical program featuresor scripts, but with generic host interface VIs or front panels. In oneembodiment, a host interface utility may be provided and used togenerate specific host interface VIs or front panels for the FPGAdiagram, and another utility may re-link them in the RT diagram.

The resulting FPGA and RT diagrams (see FIGS. 8A and 8B, describedabove) may thus explicitly represent the division of the applicationinto hardware and software targets. In another embodiment, the assistantmay generate a single system level diagram that represents the overallapplication. This single diagram may be simpler to understand than theexplicitly divided diagrams for several reasons. The completeapplication may be viewed in one diagram instead of spread across two.The explicit communication methods (and corresponding VIs) may beimplicit in the single diagram, further simplifying the actual diagram.In one embodiment, an additional tool may generate the two low leveldiagrams from the system diagram, either automatically or with guidancefrom the user. Note that the two low level diagrams (FPGA and RT) arewhat actually get deployed in the application.

Finally, as indicated in 508, the graphical program may optionally beexecuted to perform the specified functionality. For example, in oneembodiment, user input invoking execution of the graphical program maybe received, and the graphical program executed, in response to theinvoking. As noted above, in one embodiment, at least a portion of thegraphical program may be targeted for execution on a programmablehardware element. More generally, in various embodiments, variousportions of the graphical program may be targeted to respectivedifferent targets, including, for example, computers, such as computersystem 82, programmable hardware elements, such as FPGAs, PDAs, embeddedsystems, such as smart sensors, etc., and/or any other type of targetcapable of executing graphical program code. For example, differentscripts may be created specifically for generating graphical programportions or features for execution on particular targets. Alternatively,scripts may be created that are agnostic with regards to targetplatforms, but which may be configured or specified, to generategraphical program features for specific targets. In other words, thesame script may be configured to generate graphical program code aimedat different targets.

In various embodiments, the application assistant may be operable togenerate any of various types of graphical programs. For example, agenerated graphical program may be targeted toward a particulargraphical programming development environment application, e.g., toutilize proprietary features or to create files that are formatted in amanner expected by the graphical programming development environment.Examples of graphical programming development environments includeLabVIEW, BridgeVIEW, DasyLab, and DiaDem from National Instruments, VEEfrom Hewlett Packard, Simulink from The MathWorks, Softwire fromMeasurement Computing, Inc., Sanscript from Northwoods Software, WiTfrom Coreco, and Vision Program Manager from PPT Vision, among others.

In one embodiment, the application assistant may facilitate modificationof a previously created block diagram or graphical program. For example,in one embodiment, user input may be received to the GUI specifyingimport of a previously created graphical program. The previously createdgraphical program may then be imported in response to the user inputspecifying the import.

In one embodiment, configuration information for the imported graphicalprogram may be analyzed (programmatically), and the GUI may displayrespective attributes of the imported graphical program based on theanalyzing. In other words, the configuration information may be analyzedand used to populate the graphical interface elements of the GUI withappropriate data. In one embodiment, receiving user input to the GUIspecifying the functionality of the graphical program (of step 504above) may include receiving user input to at least a subset of thegraphical interface elements modifying respective attributes of theimported graphical program, where the graphical program comprises theimported graphical program. In other words, the user may then specifydesired (new) functionality for the imported graphical program, asdescribed above, where the application assistant then generates thegraphical program (i.e., the modified imported graphical program) basedon the specified functionality.

Thus, an application assistant may provide significant capabilities tothe user, allowing the user to specify functionality of applicationdomain specific graphical programs, such as timing, triggering, and I/Ofeatures for applications. As noted above, other application assistantsmay facilitate configuration or specification of different and/oradditional features.

Although the system and method of the present invention has beendescribed in connection with the preferred embodiment, it is notintended to be limited to the specific form set forth herein, but on thecontrary, it is intended to cover such alternatives, modifications, andequivalents, as can be reasonably included within the spirit and scopeof the invention as defined by the appended claims.

1. A carrier medium that stores program instructions for creating agraphical program, wherein the program instructions are executable by aprocessor to perform: displaying a graphical user interface (GUI) forspecifying functionality of a graphical program in an applicationdomain, wherein the GUI corresponds specifically to the applicationdomain; receiving user input to the GUI specifying the functionality ofthe graphical program; and generating the graphical program in responseto the user input, wherein the graphical program is executable toperform the specified functionality, wherein the graphical programcomprises a plurality of interconnected graphical program nodes thatvisually represents the functionality of the graphical program.
 2. Thecarrier medium of claim 1, wherein the user input to the GUI specifiesone or more of: timing for the graphical program; triggering for thegraphical program; analog input/output (I/O) for the graphical program;digital I/O for the graphical program; resource allocation for thegraphical program; processing options for execution of the graphicalprogram; inclusion of one or more external files in the graphicalprogram; and one or more target devices for the graphical program. 3.The carrier medium of claim 2, wherein, in specifying timing for thegraphical program, the user input specifies a timing model for thegraphical program, and wherein the GUI is operable to display agraphical representation of the timing model in response to the userinput.
 4. The carrier medium of claim 1, wherein the GUI comprises aplurality of graphical interface elements operable to indicate and/orspecify respective attributes of the graphical program.
 5. The carriermedium of claim 4, wherein the user input to the GUI specifies one ormore target devices for the graphical program, and wherein the programinstructions are further executable to perform: determining theplurality of graphical interface elements based on the specified one ormore target devices for the graphical program, wherein the plurality ofgraphical interface elements correspond to respective attributes of thegraphical program appropriate to the one or more target devices.
 6. Thecarrier medium of claim 4, wherein the program instructions are furtherexecutable to perform: determining one or more suitable target devicesfor the graphical program based on the specified functionality; the GUIindicating the one or more suitable target devices; and receiving userinput selecting at least a subset of the one or more suitable targetdevices for deployment and execution of the graphical program.
 7. Thecarrier medium of claim 1, wherein the program instructions are furtherexecutable to perform: storing configuration information for thegraphical program in one or more of: a configuration file; and thegraphical program.
 8. The carrier medium of claim 7, wherein thegraphical program comprises one or more features, wherein each of theone or more features comprises a respective one or more graphicalprogram elements; and wherein the configuration information specifiesthe graphical program at a feature level.
 9. The carrier medium of claim1, wherein the program instructions are further executable to perform:receiving user input to the GUI specifying import of a previouslycreated graphical program; and importing the previously createdgraphical program in response to the user input specifying the import.10. The carrier medium of claim 9, wherein the program instructions arefurther executable to perform: analyzing configuration information forthe imported graphical program; and the GUI displaying respectiveattributes of the imported graphical program based on said analyzingconfiguration information; wherein said receiving user input to the GUIspecifying the functionality of the graphical program comprisesreceiving user input to at least a subset of the graphical interfaceelements modifying respective attributes of the imported graphicalprogram; and wherein said generating comprises modifying the importedgraphical program based on the received user input, and wherein thegraphical program comprises the modified imported graphical program. 11.The carrier medium of claim 1, wherein the application domain comprisesone or more of: control loops; timer/counters; control; motion control;measurement; data acquisition; waveform generation; pattern matching;data analysis; image processing; signal processing; machine vision;hardware in the loop simulation; simulation; and embedded systems. 12.The carrier medium of claim 1, wherein said generating the graphicalprogram comprises: analyzing the user input; and executing one or morescripts to generate the graphical program based on the analysis.
 13. Thecarrier medium of claim 12, wherein said generating the graphicalprogram comprises: analyzing the user input; and invoking one or morelow level assistants to generate the graphical program, wherein each ofthe low level application assistants executes a respective one or morescripts to generate respective portions of the graphical program. 14.The carrier medium of claim 12, wherein said generating the graphicalprogram further comprises: generating the one or more scripts based onthe analysis.
 15. The carrier medium of claim 1, wherein said generatingthe graphical program further comprises: analyzing the user input;generating one or more data structures based on the analysis; andgenerating the graphical program based on the one or more datastructures.
 16. The carrier medium of claim 1, wherein at least aportion of the graphical program is targeted for execution on aprogrammable hardware element, and wherein the GUI is operable todisplay an estimated utilization of the programmable hardware element bythe graphical program.
 17. The carrier medium of claim 1, wherein thegraphical program is a distributed graphical program comprising a firstportion and a second portion, wherein the first portion is targeted forexecution on a first device, and wherein the second portion is targetedfor execution on a second device; and wherein the first portion and thesecond portion are respectively executable on the first device and thesecond device to perform the specified functionality in a cooperativemanner.
 18. The carrier medium of claim 17, wherein the first devicecomprises a programmable hardware element, and wherein the second devicecomprises a host computer system.
 19. The carrier medium of claim 18,wherein the GUI is operable to display an estimated utilization of theprogrammable hardware element by the first portion of the graphicalprogram.
 20. The carrier medium of claim 1, wherein the GUI is furtheroperable to perform: displaying the graphical program.
 21. The carriermedium of claim 1, wherein the GUI is further operable to perform:receiving user input specifying deployment of the graphical program toone or more target devices; and wherein the program instructions arefurther executable to perform: deploying the graphical program to theone or more target devices in response to said receiving user inputspecifying deployment of the graphical program.
 22. The carrier mediumof claim 21, wherein the GUI is further operable to perform: receivinguser input invoking execution of the graphical program; and executingthe graphical program on the one or more target devices in response tosaid invoking.
 23. A computer-implemented method for creating agraphical program, the method comprising: displaying a graphical userinterface (GUI) for specifying functionality of a graphical program inan application domain, wherein the GUI corresponds specifically to theapplication domain; receiving user input to the GUI, wherein the userinput specifies the functionality of the graphical program; andgenerating the graphical program in response to the user input, whereinthe graphical program is executable to perform the specifiedfunctionality, wherein the graphical program comprises a plurality ofinterconnected graphical program nodes that visually represents thefunctionality of the graphical program.
 24. A system for creating agraphical program, the system comprising: a processor; a memory, coupledto the processor, a display device, coupled to the processor and thememory; and an input, coupled to the processor and the memory; whereinthe memory stores program instructions which are executable by theprocessor to: display a graphical user interface (GUL) on the displaydevice for specifying functionality of a graphical program in anapplication domain, wherein the GUI corresponds specifically to theapplication domain; wherein the input is operable to: receive user inputto the GUI, wherein the user input specifies the functionality of thegraphical program; and wherein the program instructions are furtherexecutable by the processor to perform: generating the graphical programin response to the user input, wherein the graphical program isexecutable to perform the specified functionality, wherein the graphicalprogram comprises a plurality of interconnected graphical program nodesthat visually represents the functionality of the graphical program. 25.A system for creating a graphical program, the system comprising: meansfor displaying a graphical user interface (GUI) for specifyingfunctionality of a graphical program in an application domain, whereinthe GUI corresponds specifically to the application domain; means forreceiving user input to the GUI, wherein the user input specifies thefunctionality of the graphical program; and means for generating thegraphical program in response to the user input, wherein the graphicalprogram is executable to perform the specified functionality, whereinthe graphical program comprises a plurality of interconnected graphicalprogram nodes that visually represents the functionality of thegraphical program.